DE3342631A1 - THIENOTHIOPHENE DERIVATIVES - Google Patents

Abstract

Thienothiophene derivatives of the formula I R1-(A1)m-Z1-A-(Z2-A2)n-R2 I in which R1 and R2 are each H or an alkyl group having 1-12 C atoms, in which, furthermore, one or two non-adjacent CH2 groups can be replaced by O atoms, -CO- or -CH=CH- groups, or are each F, Cl, Br, CN, -COOR or -O-COR, A1 and A2 are each 1,4-phenylene, 1,4-cyclohexylene, 1,3-dioxane-2,5-diyl, 1,3-dithiane-2,5-diyl, tetrahydropyran-2,5-diyl, pyridazine-3,6-diyl or the corresponding N-oxide, piperidine-1,4-diyl, 1,4-bicyclo[2.2.2]octylene or pyrimidine-2,5-diyl groups which are unsubstituted or substituted by one or two F, Cl or Br atoms and/or CN groups and/or CH3 groups, A is a group of the formula 1 or 2 <IMAGE> which is unsubstituted or substituted by one or two Cl and/or Br atoms, Z1 and Z2 are each -CO-O-, -O-CO-, -CH2CH2-, -OCH2+13, -CH2O- or a single bond, R is an alkyl group having 1-10 C atoms, m is 1 or 2 and n is 0 or 1, and where m is 2, the two groups A1 can be identical or different, can be used as components of liquid crystalline phases.

Description

Merck patent limited liability company Darmstadt

Thienothiophene extracts

The invention relates to new thienothiophene extracts of the formula I.

11 1 7 7 0

^R (A> _m - ^z "Α"< ^z - ^A > n ~ ^R

worxn

1 2
R and R each H, exne alkyl group mxt 1-10 C-

Atoms in which one or two groups have also been replaced by O atoms can, F, Cl, Br, CN, -COOR or -O-COR,

PAT LOG 3/5 270983

and A are each unsubstituted or by

one or two F, Cl, Br atoms and / or CN groups and / or CH ₃ groups substituted 1,4-phenylene, 1,4-cyclohexylene, 1,3-dioxane-2,5- diyl-, 1,3-dithiane-2,5-diyl, tetrahydropyran-2,5-diyl, pyridazine-3,6-diyl, piperidine-1,4-diyl-, 1,4-bicyclo (2.2, 2) -octylene or pyrimidine-2,5-diyl groups, an unsubstituted group of the formula 1 or 2 which is substituted by one or two Cl and / or Br atoms

Z ¹ and Z ² each -CO-O-, -0-C0-, -CH ₂ CH ₂ -, -

-CH ₂ O- or a single bond, R is an alkyl group with 1-10 C atoms, m 1 or 2 and
η 0 or 1
mean,

where for m = 2 the two groups A can be identical to or different from one another.

PAT EOG 3/5 270983

-t -

For the sake of simplicity, in the following Phe means a 1,4-phenylene group, Cy a 1,4-cyclohexylene group, Dio a 1,3-dioxane-2,5-diyl group, Bi a bicyclo- (2,2,2) -octylene group, Pip a piperidine-1,4-diyl group, and Pyr a pyrimidine-2,5-diyl group, these groups, in particular the 1,4-phenylene group and / or the 1,4-cyclohexylene group, being unsubstituted or by one or two F and / or Cl and / or Br atoms and / or CN groups and / or CH ₃ groups can be substituted.

The compounds of the formula I, like similar compounds, can be used as components of liquid-crystalline dielectrics are used, especially for displays based on the principle of the twisted cell, the guest-host effect, the effect of deformation of erect phases or the effect of dynamic scattering.

The invention was based on the object of finding new stable liquid-crystalline or mesogenic compounds, which are suitable as components of liquid-crystalline phases.

It has been found that the compounds of the formula I are eminently suitable as components of liquid-crystalline phases are. In particular, they are used to create stable liquid-crystalline phases with positive or negative ones dielectric anisotropy, broad nematic ranges and comparatively low viscosity.

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. G-

With the provision of the compounds of the formula I, the range of liquid-crystalline substances, which are classified under various application-related aspects of production nematic mixtures are suitable, considerably broadened.

The compounds of the formula I have a wide range of applications. Depending on the choice of Substituents can use these compounds as base materials serve, from which liquid-crystalline phases are predominantly composed; it can but also compounds of the formula I added to liquid-crystalline base materials from other classes of compounds be, for example, the dielectric and / or optical anisotropy of such a phase vary. The compounds of the formula I are also suitable as intermediates for the preparation of others Substances that can be used as components of the liquid-crystalline phase.

The compounds of the formula I are colorless in the pure state and form liquid-crystalline mesophases in a temperature range that is conveniently located for electro-optical use. Chemical, thermal and they are very stable against light.

The invention thus relates to the compounds of the formula I and a process for their preparation, characterized in that a compound which otherwise corresponds to formula I, but instead of H atoms contains one or more reducible groups and / or C-C bonds, with a reducing agent treated,

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or that for the preparation of esters of the formula I

1 2

(where R and / or R are -O-COR or -COOR

1 7

and / or where Z and / or Z are -CO-O- or -0-C0-) a corresponding carboxylic acid or one of its reactive derivatives with a corresponding one Converts alcohol or one of its reactive derivatives,

or that one can produce dioxane derivatives

1 2 of the formula I (in which A and / or A are 1,3-dioxane-2,5-diyl mean) reacts a corresponding aldehyde with a corresponding diol,

or that for the production of nitriles the

1 2 Formula I (in which R and / or R are CN) dehydrated a corresponding carboxamide or a corresponding carboxylic acid halide reacts with sulfamide,

or that a thiophene derivative of the formula II,

W Il
25th

wherein
c

1 2
one of the residues Q and Q -CHO, the other

-SCH ₂ -Cj and Q "R- (A" ¹ ") _m ~ Z - or R- (AZ") _n means condensed,

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or that for the production of ethers of the form

1 2

mel I (where R and / or R is an alkyl group, wherein one or two CHL groups through

I 2 O atoms are replaced and / or Z and / or 2 is an -OCH ₂ - or -CE-O- group) etherifies a corresponding hydroxy compound,

and / or that optionally a chlorine or bromine compound of the formula I (in which R and / or 2
R is Cl or Br) with a cyanide.

The invention also relates to the use of the compounds of the formula I as components liquid crystalline phases.

The invention also relates to liquid-crystalline phases with a content of at least a compound of the formula I and liquid crystal display elements, especially electro-optical ones Display elements that contain such phases.

12 12 Before and below R, R, R, A, A, A, 12 12 3

Z, Z, m, n, Q, Q and Q have the meanings given, unless expressly stated otherwise is noted.

The compounds of the formula I accordingly include compounds of the sub-formulas Ia (with two rings), Ib and Ic (each with three rings) and Id (with four rings):
30th

R ¹ -A ¹ -Z ¹ -AR ² Ia

_R ¹ ^ _A ¹ _Z ¹ -AZ ² -A ² -R ² Ib

R ¹ - (A ¹ ) ₂ -Z ¹ -AR ² Ic

R ¹ - (A ¹ > ₂ -Z ¹ -AZ ² -A ² -R ² Id.

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The preferred compounds of sub-formula Ia include those of sub-formulas Ie to Ij:

R ¹ -Phe-Z ¹ -AR ² Ie

R ^ Cy-Z ^ AR ² If

R ¹ -Dio-Z ¹ -AR ² Ig

R ¹ -Pip-Z ¹ -AR ² Ih

R ¹ -Bic-Z ¹ -AR ² Ii

1 12

R -Pyr-Z -A-R Ij

Of these, those of the formulas Ie, If and Ig are special preferred.

Of the compounds of the sub-formulas Ib, Ic and Id, those of the sub-formulas Ik to Iz are particularly preferred:

R ¹ -Phe-Z ¹ -AZ ² -Phe-R ² Ik

R ¹ -Dio-Z ¹ -AZ ² -Cy-R ² II

R ¹ -Cy-Z ¹ -AZ ² -Phe-R ² Im

R ¹ -Cy-Z ¹ -AZ ² -Cy-R ² In

R ¹ -Phe-Phe-Z ¹ -AR ² Io

R ^ Phe-Cy-Z ^ AR ² Ip

R ¹ -Cy-Phe-Z ¹ -AR ² Ig

R ¹ -Cy-Cy-Z ¹ -AR ² Ir

R ¹ -Phe-Phe-Z ¹ -AZ ² -Phe-R ² Is

R ¹ -Phe-Phe-Z ¹ -AZ ² -Cy-R ² It

R ¹ -Phe-Cy-Z ¹ -AZ ² -Phe-R ² Iu

R ¹ -Phe-Cy-Z ¹ -AZ ² -Cy-R ² Iv

R ¹ -Cy-Phe-Z ¹ -AZ ² -Phe-R ² Iw

R ¹ -Cy-Phe-Z ¹ -AZ ² -Cy-R ² Ix

R ¹ -Cy-Cy-Z ¹ -AZ ² -Phe-R ² Iy

R ¹ -Cy-Cy-Z ¹ -AZ ² -Cy-R ² , Iz

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In the compounds of the formulas above and below

1 2
R and R, which can be the same or different, are preferably alkyl, furthermore alkoxy (especially if these radicals are on a Phe group) or another oxaalkyl group.

Compounds of the formula I are also preferred

l 2
wherein one of the radicals R and R is halogen, in particular F, or CN.

1 2
A and A are preferably Cy or Phe, furthermore preferred

Dio or Pip; the compound of the formula I preferably contains no more than one of the radicals Dio, Pip, Bic or Pyr.
15th

Also preferred are compounds of the formula I which contain at least one cycloaliphatic ring (Cy, Dio, Bi or Pip) included.

A is preferably an unsubstituted group of the formula 1 or 2.

1 2
Z and Z, which can be the same or different, are preferably single bonds, in the second place preferably —CO — O or —O — CO groups.

m is preferably 1, η is preferably 0.

If R and / or R denote alkyl radicals in which one (“alkoxy” or “oxaalkyl”) or two (“alkoxyalkoxy” or “dioxaalkyl”) CH ₂ groups can be replaced by O atoms, they can be straight-chain or branched. They are preferably straight-chain, have 2, 3, 4, 5, 6 or 7 carbon atoms and are therefore preferably ethyl, propyl, butyl, pentyl, hexyl, heptyl, ethoxy,

PAT LOG 3/5 270.983 ..

Propoxy, butoxy, pentoxy, hexoxy, heptoxy, 2-oxapropyl (= Methoxymethyl), 2- (= ethoxymethyl) or 3-0xabutyl (= 2-methoxyethyl), 2-, 3- or 4-oxapentyl, 2-, 3-, 4- or 5-0xahexyl, 2-, 3-, 4-, 5- or 6-oxaheptyl, also methyl, octyl, nonyl, decyl, methoxy, octoxy, Nonoxy, decoxy, 2-, 3-, 4-, 5-, 6- or 7-oxaoctyl, 2-, 3-, 4-, 5-, 6-, 7- or 8-0xanonyl, 2-, 3- , 4-, 5-, 6-, 7-, 8- or 9-oxadecyl, 1,3-dioxabutyl (= Methoxymethoxy), 1,3-, 1,4- or 2,4-dioxapentyl, 1,3-, 1,4-, 1,5-, 2,4-, 2,5- or 3,5-dioxahexyl, 1,3-, 1,4-, 1,5-, 1,6- , 2.4-, 2.5-, 2.6-, 3.5-, 3.6- or 4,6-dioxaheptyl.

Also preferred are compounds of the formula I in which

2
R an alkylre!

Atoms means.

2
R is an alkyl radical or an alkoxy radical with 3 to 7 C-

Compounds of the formulas I and Ia to lap with various

1 2 branched wing groups R or R can occasionally be of importance because of better solubility in the usual liquid-crystalline base materials, in particular but as chiral dopants when they are optically active. Branched groups of this type contain in usually no more than a chain branch. Before-

1 2
Added branched radicals R and R are isopropyl, 2-butyl (= 1-methylpropyl), isobutyl (= 2-methylpropyl), 2-methylbutyl, isopentyl (= 3-methylbutyl), 2-methylpentyl, 3-methylpentyl, 2-ethylhexyl , 2-propylpentyl, isopropoxy, 2-methylpropoxy, 2-methylbutoxy, 3-methylbutoxy, 2-methylpentoxy, 3-methylpentoxy, 2-ethylhexoxy, 1-methylhexoxy, 1-methylheptoxy, 2-oxa-3-methylbutyl, 3-oxa -4-methylpentyl.

In the radicals R are the alkyl groups or alkoxy groups likewise preferably straight-chain and are in particular methyl or ethyl, furthermore propyl, butyl or Pentyl.

PAT LOG 3/5 270983

Of the compounds of the formulas I and Ia to Iz, those are preferred in which at least one of the radicals contained therein has one of the preferred meanings given. Particularly preferred smaller ones Groups of compounds are those of the formulas Iaa to Iat:

R ^3- -A ^3- -Z ^3- -AR ² Iaa

R ¹ -Phe-Z ¹ -AR ² lab

R ^3- -PlIe-AR ² Iac

R ^3- -PlIe-CO-OAR ² lad

R ³ -PlIe-O-CO-AR ² Iae

R ³ -PlIe-CH ₂ CH ₂ -AR ² Iaf

R ³ -PlIe-O-CH ₂ -AR ² was

R ^3- -PlIe-CH ₇ -OAR ² Iah

1 12
R-Cy-ZAR Iai

R ^3- -Cy-AR ² Ia j

R ^3- -Cy-CO-OAR ² Iak

R ³ -Cy-O-CO-AR ² IaI

R ³ -Cy-CH ₂ CH ₂ -AR ² I am

R ³ -Cy-O-CH ₂ -AR ² lan

R ³ -Cy-CH ₂ -OAR ² Iao

R ^3- DiO-AR ² lap

R ³ -PiP-AR ² Iaq

R ^3- -BiC-AR ² I ar

R ^3- -PYr-AR ² las

R ¹ -Phe-Phe-AR ² Iat.

Among the compounds of the formula I, which are 1,4-cyclohexylene, 1,3-dioxane-2,5-diyl, 1,3-dithiane-2,5-diyl, tetrahydropyran-2,5-diyl and / or contain piperidine-1,4-diyl group, those are preferred in which these groups are transubstituted.
35

PAT LOG 3/5

Those of the above formulas which contain one or more of the groups Dio, Pip and / or Pyr contain, each enclose the two possible 2,5- and 1,4-positional isomers. So both

1 2 for example the partial formula lap the 2-R -5- (A-R) -

2 1 1,3-dioxanes and the 2- (A-R) -5-R -1,3-dioxanes, the

1 2

Sub-formula Iaq the 1-R -4- (A-R) -piperidines and the

2 1
1- (AR) -4-R -piperidines.

If compounds of the formula I have branched wing groups R ₁ and / or R ₂ , formula I includes both the racemates and the optical antipodes and mixtures thereof.

The compounds of the formula I are prepared by methods known per se, as described in the literature (e.g. in the standard works such as Houben-Weyl, Methods of Organic Chemistry, Georg-Thieme-Verlag, Stuttgart) are described, under reaction conditions which are known and suitable for the reactions mentioned are. Use can also be made here of variants which are known per se but are not mentioned here in greater detail.

In principle, all methods can be used in the synthesis of the starting materials, on the one hand for the compounds of the formula I are known which carry other groups in place of group A, or on the other hand for the thiophene derivatives of the formula II

1 2 are known that carry other radicals in place of the radicals Q, Q and / or Q. The skilled person can do the necessary Derive synthesis variants according to routine methods.

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If desired, the starting materials can also be used in situ are formed in such a way that they are not isolated from the reaction mixture, but immediately on to the Compounds of formula I converts. 5

Thus, the compounds of the formula I can be prepared by adding a compound that is otherwise of the formula I corresponds, but instead of Η atoms one or more reducible groups and / or C-C bonds contains, reduced.

Preferred reducible groups are carbonyl groups, in particular keto groups, and also, for example, free or esterified hydroxyl groups or aromatically bonded halogen atoms. Preferred starting materials for the reduction correspond to formula I, but instead of a cyclohexane ring can be a cyclohexene ring or cyclohexanone ring and / or instead of a -CH ₂ CH - group a -CH = CH group and / or instead of a -CH_ group contain a -CO group and / or instead of a Η atom a free or a functionally modified (eg in the form of its p-toluenesulfonate) OH group.

The reduction can be carried out, for example, by hydrogenating corresponding sulfonates or halides with zinc and an acid (e.g. glacial acetic acid, hydrochloric acid) or with complex hydrides (e.g. with NaBH ₄ , expediently in a solvent such as dimethyl sulfoxide or with LiAlH ₄ , expediently in a solvent such as diethyl ether, Dioxane, tetrahydrofuran). The reduction is preferably carried out at temperatures between about 0 ° and about 100 °.

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-VB-

The sulfonates or halides are, for example, from the corresponding methods known from the literature Alcohols obtainable, which in turn are accessible by reducing the corresponding ketones. links with reducible C-C bonds can be converted into dihalides by methods known from the literature, which can then be dehalogenated by the processes mentioned.

Ketones can also be prepared by the methods of Clemmensen (with zinc, amalgamated zinc or tin and hydrochloric acid, expediently in an aqueous-alcoholic solution or in a heterogeneous phase with water / toluene at temperatures between about 80 and 120 °) or Wolff-Kishner (with hydrazine, expediently in the presence of alkali such as KOH or NaOH in a high-boiling solvent such as diethylene glycol or triethylene glycol at temperatures between about 100 and 200 °) to the corresponding compounds of the formula I containing alkyl groups and / or -CH ₂ CH ₂ bridges .

12 1

Esters of the formula I (R and / or R = -O-COR or Z

2
and / or Z = -CO-O- or -0-CO-) can also by

Esterification of corresponding carboxylic acids of the formulas R-COOH, R ^3- - (A ¹ ) -COOH, R ¹ - (A ¹ JZ ^3- -A-COOH, R ² - (A ² ) -COOH

α r \ λ Ift ΙΠ IX

or R - (A -Z) -A-COOH (or their reactive derivatives) with alcohols or phenols of the formulas

R ^1- - (A ¹ ) -Z ^3- -A- (Z ² -A ² ) -OH, R ² - (A ² -Z ² ) -AZ ^3- - (A ¹ ) -OH,

9 7 7 2 9 111

R- (AZ ^ JA-OH, R- (A ^Z ) -OH, R ^4- - (A VZA-OH or

«Ι ^ XJi XX XIl

R - (A) -OH (or their reactive derivatives) can be obtained.

PAT LOG 3/5 270983

-VS-

The acid halides, especially the chlorides and bromides, and also the anhydrides, for example also mixed anhydrides of the formulas R - (A) -CO-O-COCH ₃₁ R ¹ - (A ¹ JZ ^3- -A-CO-O-COCH ,, R ² - (A ² ) -CO-O-COCH, and

λ λ XIIm O Il Ö

R - (A -ZJ _n -A-CO-O-COCH ₃ , azides or esters, especially alkyl esters with 1-4 carbon atoms in the alkyl group.

As reactive derivatives of the alcohols mentioned or Phenols come in particular the corresponding metal alcoholates or phenolates of the formulas

R ¹ - (A ¹ 1-Z ^3- -A- (Z ² -A ² ) -OM, R ² - (A ^ Z ² JAZ ¹ - (A ¹ ) -OM, 99 ^m ? ?? 111

R- (A ^ -ΊΓ ) -A-OM, R- (A ^) -OM, ΈΓ- (Α ^Χ ) -Z -A-OM and -1 - | n 11 m

R- (A) _m -0M into consideration, in which M is an equivalent of a metal, preferably an alkali metal such as Na or K.

The esterification is advantageously carried out in the presence of an inert solvent. Are well suited in particular ethers such as diethyl ether, di-n-butyl ether, THF, dioxane or anisole, ketones such as acetone, butanone or cyclohexanone, amides such as DMF or phosphoric acid hexamethyltriamide, Hydrocarbons such as benzene, toluene or xylene, halogenated hydrocarbons such as tetra-chlorocarbon or tetrachlorethylene and sulfoxides such as dimethyl sulfoxide or sulfolane. Not with water Miscible solvents can at the same time be advantageous for the azeotropic distillation of the during the esterification formed water can be used. Occasionally, an excess of an organic base, e.g. pyridine, Quinoline or triethylamine as solvents for the

PAT LOG 3/5 270983

Esterification can be applied. The esterification can also in the absence of a solvent, e.g. by simply heating the components in the presence of sodium acetate, be performed. The reaction temperature is usually between -50 ° and + 250 °, preferably between -20 ° and +80 °. At these temperatures, the esterification reactions are usually after 15 minutes finished within 48 hours.

In particular, the reaction conditions for the esterification depend largely on the nature of the one used Starting materials. Thus, a free carboxylic acid is usually present with a free alcohol or phenol a strong acid, for example a mineral acid such as hydrochloric acid or sulfuric acid. A preferred mode of reaction is the conversion of an acid anhydride or, in particular, an acid chloride with an alcohol, preferably in a basic medium, with alkali metal hydroxides in particular as bases such as sodium or potassium hydroxide, alkali metal carbonates or hydrogen carbonates such as sodium carbonate, sodium hydrogen carbonate, potassium carbonate or Potassium hydrogen carbonate, alkali metal acetates such as sodium or potassium acetate, alkaline earth metal hydroxides such as calcium hydroxide or organic bases such as triethylamine, pyridine, lutidine, collidine or quinoline are of importance are. Another preferred embodiment of the Esterification consists in first converting the alcohol or the phenol into the sodium or potassium alcoholate or phenolate, e.g. by treatment with ethanolic sodium or potassium hydroxide solution, this is isolated and together with sodium hydrogen carbonate or

PAT LOG 3/5 270983

Suspended potassium carbonate with stirring in acetone or diethyl ether and this suspension with a Solution of the acid chloride or anhydride in diethyl ether, acetone or DMF added, expediently at temperatures between about -25 ° and +20 °.

Dioxane derivatives of the formula I (in which one of the groups

1 2

A and / or A is a 1,3-dioxane-2,5-diyl group) are expediently obtained by reaction of a corresponding aldehyde, for example of the formulas R - (A) ^ ₁ -CHO, R ^1- - (A ¹ ) -Z ¹ -AZ ² -CHO, O = CH- (A ¹ ) - -Z ^3- -A- (Z -A ² ) -R ²

ItI λ Hl ^ JL XX

or O = CH-R (or one of its reactive derivatives) with a corresponding 1,3-diol e.g.

of the formulas (HOCH ₀ J ₀ CH- (A ¹ ) -.- Z ^1- -A- (Z ² -A ² ) -R ² , _, ζ Z ₁ mj. η -

(HOCH ₂ J ₂ CH-R, R - (A ^ _-1 -CH (CH ₂ OH) ₂ or R- (A ^χ ) Z -AZ CH (CH ₂ OH) ₂ (or one of its reactive derivatives) , preferably in the presence of an inert solvent such as benzene or toluene and / or a catalyst, for example a strong acid such as sulfuric acid, benzene or p-toluenesulfonic acid, at temperatures between about 20 ° and about 150 °, preferably between 80 ° and 120 °. Primarily suitable reactive derivatives of the starting materials are acetals, for example of the form in R ^3- (A ¹ ) -, CH (OR ³ J ₀ , R ^1- (A ¹ ) -Z ^1- -AZ ² -CH (OR ³ ), (R ^J 0) _o CH- (A- ^L ) _m -Z ^ -A-iZ ^ -A ^) -R ^, (R ^J O) -R ^,

4 ^zm ~ ^x χ ι 2 2 2 4 R -CH (OCH ₂ ) ₂ CH- (A) _m _ ₁ -Z -A- (Z ^ -A ^ J _n -R ^, R-

CH (OCH ₂ ) ₂ CH-R ² , R- ¹ ^ - (A ¹ "J _1n-1 -CH (CH ₂ O) ₂ CH-R ⁴ or R ^1- (A ¹ ) -Z ^1- -AZ ¹ CH (CH ₀ O) ₀ CHR ⁴ , in which R ^{3 is} alkyl with 1-4 C atoms, two radicals R together as well

4 denotes alkylene with 2 or 3 carbon atoms and R is H, alkyl with 1-4 carbon atoms or phenyl.

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Some of the aldehydes and 1,3-diols mentioned and their reactive derivatives are known, and some of them can be prepared from compounds known from the literature without difficulty by standard methods of organic chemistry. For example, the aldehydes can be obtained by oxidation of corresponding alcohols or by reduction of corresponding carboxylic acids or their derivatives, the diols by reduction of corresponding diesters.
10

For the preparation of nitriles of the formula I (in which R

2 12

and / or R denotes CN and / or in which A and / or A is substituted by at least one CN group), corresponding acid amides, for example those in which a CONH ₂ group takes the place of the radical X, can be dehydrated. The amides can be obtained, for example, from corresponding esters or acid halides by reaction with ammonia. Inorganic acid chlorides such as SOCl ₂ , PCl ₃ , PCl ₅ , POCl ₃ , SO ₃ Cl ₂ , COCl ₂ , and also P ₂ ⁰ S ' ^P 2 ^S 5' ^A "*" ^C ^ 3 ( ^Ζ · ^Β · ^a ^ - ^s double compound with NaCl), aromatic sulfonic acids and sulfonic acid halides. You can work in the presence or absence of an inert solvent at temperatures between about 0 ° and 150 °; Suitable solvents are, for example, bases such as pyridine or triethylamine, aromatic hydrocarbons such as benzene, toluene or xylene, or amides such as DMF.

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To prepare the above-mentioned nitriles of the formula I, corresponding acid halides, preferably the chlorides, react with sulfamide, expediently in an inert solvent such as tetramethylene sulfone at temperatures between about 80 ° and 150 °, preferably at 120 °. After the usual work-up you can isolate the nitriles directly.

Compounds of the formula I are also available by adding a thiophene derivative of the formula II,

■■

1 2 wherein one of the radicals Q and Q -CHO, the other -SCH ₀ -Q ³ and Q ³ R ^3- - (A ¹ ) -Z ¹ - or R ² - (A ² -Z ² ) - be-2 m η

indicates, condenses.

The preparation of the compounds of the formula II and their condensation can be carried out according to known methods Methods are carried out as described in the literature [e.g.

VP Litvinov and Ya.L. Gold ¹ color, Izv.Akad.Nauk. SSSR, Ser. Khim., 2183 (1963)], under reaction conditions which are known and suitable for the reactions mentioned. Use can also be made here of variants which are known per se and are not mentioned here in greater detail.

PAT LOG 3/5 270983

- TA -

1 2

Ethers of the formula I (in which R and / or R denotes an alkyl group in which one or two CH ₉ groups pass through

l 2 O atoms are replaced, and / or in which Z and / or Z is an -OCH ₂ - or a -C ^ O group) can be obtained by etherification of corresponding hydroxy compounds, preferably corresponding phenols, the hydroxy compound being expediently initially in a corresponding metal derivative, for example by treatment with NaH, NaNH ₂ , NaOH, KOH, Na ₂ CO ₃ or K ₂ CO ₃ , is converted into the corresponding alkali metal alcoholate or alkali metal phenate. This can then be reacted with the corresponding alkyl halide, sulfonate or dialkyl sulfate, expediently in an inert solvent such as acetone, 1,2-dimethoxyethane, DMF or dimethyl sulfoxide or an excess of aqueous or aqueous-alcoholic NaOH or KOH at temperatures between about 20 ° and 100 °.

For the preparation of nitriles of the formula I (in which R

2

and / or R is CN and / or in which A and / or A is substituted by at least one CN group) corresponding chlorine or bromine compounds can also

1 2

gene of the formula I (in which R and / or R Cl or Br

1 2

mean and / or where A and / or A is substituted by at least one Cl or Br atom) are reacted with a cyanide, expediently with a metal cyanide such as NaCN, KCN or Cu ₃ (CN) ₂ , for example in the presence of pyridine in an inert solvent such as DMF or N-methylpyrrolidone at temperatures between 20 ° and 200 °.

PAT LOG 3/5 270983

- as -

The liquid-crystalline phases according to the invention consist of 2 to 15, preferably 3 to 12 components, including at least one compound of the Formula I. The other ingredients are preferably selected from nematic or nematogenic Substances, in particular the known substances from the classes of azoxybenzenes, benzylidene anilines, Biphenyls, terphenyls, phenyl or cyclohexyl benzoates, cyclohexanecarboxylic acid phenyl or cyclohexyl esters, phenylcyclohexanes, cyclohexylbiphenyls, Cyclohexylcyclohexane, cyclohexylnaphthalenes, 1,4-bis-cyclohexylbenzenes, 4,4'-biscyclohexylbiphenyls, Phenyl- or cyclohexylpyrimidines, phenyl- or cyclohexyldioxanes, optionally halogenated stilbenes, benzyl phenyl ethers, tolanes and substituted cinnamic acids.

The most important compounds that can be used as constituents of such liquid-crystalline phases can be characterized by the formula VI,

R'-L-G-E-R "VI

wherein L and E each have a carbo- or heterocyclic ring system from the 1,4-disubstituted benzene and cyclohexane rings, 4,4'-disubstituted biphenyl, phenylcyclohexane and cyclohexylcyclohexane systems, 2,5-disubstituted pyrimidine and 1,3-dioxane rings, 2,6-disubstituted naphthalene, di- and tetrahydronaphthalene, Quinazoline and tetrahydroquinazoline formed group,

PAT LOG 3/5 270983

• 25- κ »* - · * <* · m
334263 - 2 «- -CH = CH- -N (O) = N- -CH = CY- -CH = N (O) - -C = C- -CH ₂ -CH ₂ - -CO-O- -CH ₂ -O- -CO-S- -CH ₂ -S- -CH = N- -COO-Phe-COO-

or a CC single bond, Y halogen, preferably chlorine, or -CN, and R ¹ and R "alkyl, alkoxy, alkanoyloxy or alkoxycarbonyloxy with up to 18, preferably up to 8 carbon atoms, or one of these radicals also CN, NC, NO ₂ , CF-, F, Cl or Br mean.

In most of these compounds, R ¹ and R ″ are different from one another, one of these radicals usually being an alkyl or alkoxy group. However, other variants of the substituents provided are also common. Many such substances or mixtures thereof are commercially available. All of these Substances can be produced by methods known from the literature.

The phases according to the invention contain about 0.1 to 100, preferably 10 to 100%, of one or more compounds of the formula I. Also preferred Phases according to the invention containing 0.1 to 70, in particular 0.5 to 60%, of one or more compounds of formula I.

The phases according to the invention are produced in a manner which is customary per se. Usually be the components dissolved in one another, expediently at an elevated temperature.

PAT LOG 3/5 270983

-Vf-

The liquid-crystalline Phases according to the invention are modified so that they are in all previously known Types of liquid crystal display elements can be used.

Such additives are known to the person skilled in the art and are described in detail in the literature. For example, conductive salts, preferably ethyl dimethyl dodecyl ammonium 4-hexyloxybenzoate, tetrabutylammonium tetraphenylboranate or complex salts of crown ethers (cf., for example, I. Haller et al., Mol.Cryst.Liq.Cryst. Volume 24, pages 249-258 (1973)) to improve the conductivity, dichroic dyes for the production of colored guest-host systems or substances for changing the dielectric anisotropy, the viscosity and / or the orientation of the nematic phases can be added. Such substances are described, for example, in DE-OS 22 09 127, 22 40 864, 23 21 632, 23 38 281, 24 50 088, 26 37 430, 28 53 728 and 29 02 177.

The following examples are intended to illustrate the invention without limiting it. F. = melting point, K. = clearing point. Above and below, percentages are percentages by weight; all temperatures are in degrees Celsius specified. “Customary work-up” means: one adds water, extracts with methylene chloride, separates off, the organic phase dries, evaporates and the product is purified by crystallization and / or chromatography.

PAT LOG 3/5 270983

ι ο

example 1

3.5 g of 5-n-pentyl-thieno [3,2-b] thiophene-2-carboxylic acid chloride [obtainable by reacting 5-n-pentylthieno [3,2-b] thiophene-5-carboxylic acid (F. 156 °, K. 196 °) with thionyl chloride] in 20 ml of toluene is added dropwise to a mixture of 2.25 g of 4-n-pentylphenol, 1.08 g of pyridine and 30 ml of toluene, heated to the boil for 2 hours, allowed to cool, filtered off the pyridine hydrochloride and works as usual on. 5-n-Pentyl-thieno [3,2-b] thiophene-2-carboxylic acid 4-n-pentylphenyl ester is obtained, F. 58 °, K. 93 '

The following are produced in the same way:

5-Pentyl-thieno [3,2-b] thiophene-2-carboxylic acid 4-ethylphenyl ester

5-Pentyl-thieno [3,2-b] thiophene-2-carboxylic acid 4-propylphenyl ester

5-Pentyl-thieno [3,2-b] thiophene-2-carboxylic acid 4-butylphenyl ester

5-Pentyl-thieno [3,2-b] thiophene-2-carboxylic acid 4-heptylphenyl ester

5-Propyl-thieno [3,2-b] thiophene-2-carboxylic acid 4-ethylphenyl ester

5-propyl-thieno [3,2-b] thiophene-2-carboxylic acid 4-propylphenyl ester

5-Propyl-thieno [3,2-b] thiophene-2-carboxylic acid 4-buty / phenyl ester
5-propyl-thieno [3,2-b] thiophene-2-carboxylic acid 4-p entylphenyl ester

5-propyl-thieno [3,2-b] thiophene-2-carboxylic acid 4-heptylphenyl ester

PAT LOG 3/5 270983

5-Butyl-thieno [3,2-b] thiophene-2-carboxylic acid 4-ethylphenyl ester

5-Butyl-thieno [3,2-b] thiophene-2-carboxylic acid 4-propylphenyl ester

5-Butyl-thieno [3,2-b] thiophene-2-carboxylic acid 4-butylphenyl ester

5-Butyl-thieno [3,2-b] thiophene-2-carboxylic acid 4-pentylphenyl ester

5-Butyl-thieno [3,2-b] thiophene-2-carboxylic acid 4-heptylphenyl ester

5-Heptyl-thieno [3,2-b] thiophene-2-carboxylic acid 4-ethylphenyl ester

5-Heptyl-thieno [3,2-b] thiophene-2-carboxylic acid 4-propylphenyl ester

5-Heptyl-thieno [3,2-b] thiophene-2-carboxylic acid 4-butylphenyl ester

5-Heptyl-thieno [3,2-b] thiophene-2-carboxylic acid 4-pentylphenyl ester
5-Heptyl-thieno [3,2-b] thiophene-2-carboxylic acid 4-heptylphenyl ester

5-Nonyl-thieno [3,2-b] thiophene-2-carboxylic acid 4-ethylphenyl ester
5-Nonyl-thieno [3,2-b] thiophene-2-carboxylic acid-4-propylphenyl ester

5-Nonyl-thieno [3,2-b] thiophene-2-carboxylic acid 4-butylphenyl ester

5-Nonyl-thieno [3,2-b] thiophene-2-carboxylic acid 4-pentylphenyl ester

5-Nonyl-thieno [3,2-b] thiophene-2-carboxylic acid 4-heptylphenyl ester

PAT LOG 3/5 270983

5-propyl-thieno [3,2-b] thiophene-2-carboxylic acid 4-cyanophenyl ester

5-Butyl-thieno [3,2-b] thiophene-2-carboxylic acid 4-cyanophenyl ester

5-Pentyl-thieno [3,2-b] thiophene-2-carboxylic acid 4-cyanophenyl ester, m.p. 98 °, K. 137 °
5-Hexyl-thieno [3,2-b] thiophene-2-carboxylic acid 4-cyano-phenyl ester

5-Heptyl-thieno [3,2-b] thiophene-2-carboxylic acid 4-cyanophenyl ester

5-Nonyl-thieno [3,2-b] thiophene-2-carboxylic acid 4-cyanophenyl ester

5-Pentyl-thieno [3,2-b] thiophene-2-carboxylic acid 4-fluorophenyl ester

5-Pentyl-thieno [3,2-b] thiophene-2-carboxylic acid 4-chlorophenyl ester

5-Pentyl-thieno [3,2-b] thiophene-2-carboxylic acid 4-bromophenyl ester
. 5-Pentyl-thieno [3,2-b] thiophene-2-carboxylic acid 4-methoxyphenyl ester

5-Pentyl-thieno [3,2-b] thiophene-2-carboxylic acid 4-ethoxyphenyl ester

5-Pentyl-thieno [3,2-b] thiophene-2-carboxylic acid 4-propoxyphenyl ester

5-Pentyl-thieno [3,2-b] thiophene-2-carboxylic acid 4-butoxyphenyl ester

5-Pentyl-thieno [3,2-b] thiophene-2-carboxylic acid-4-pentoxyphenyl ester
5-Pentyl-thieno [3,2-b] thiophene-2-carboxylic acid 4-heptoxyphenyl ester

5-Pentyl-thieno [3,2-b] thiophene-2-carboxylic acid 4-nonoxyphenyl ester

PAT LOG 3/5 270983

5-Pentyl-thieno [3,2-b] thiophene-2-carboxylic acid 4'-propylbiphenylyl ester

5-pentyl-thieno [3,2-b] thiophene-2-carboxylic acid-4'-cyanob iphenyIy1ester

5-Pentyl-thieno [3,2-b] thiophene-2-carboxylic acid 2'-fluoro-4'-ethylbiphenylyl ester 5-Pentyl-thieno [3,2-b] thiophene-2-carboxylic acid 2-methyl-4'-propylbiphenylyl ester 5-Pentyl-thieno [3,2-b] thiophene-2-carboxylic acid 4- (4-propylcyclohexyl) phenyl ester 5-Pentyl-thieno [3,2-b] thiophene-2-carboxylic acid 4- (1-cyano-4-propylcyclohexyl) phenyl ester 5-Pentyl-thieno [3,2-b] thiophene-2-carboxylic acid 4- (5-propyl-1,3-dioxan-2-yl) phenyl ester.

PAT LOG 3/5 270983

Example 2

5.75 g of 2- [2- (trans-5-n-pentylcyclohexyl) -acetyl] -5-n-pentylthieno [3,2-b] thiophene [obtainable by reacting 5-n-pentylthieno [3,2-b] thiophene-2-carbonitrile (from the acid chloride by reaction with ammonia and subsequent dehydration of the amide with thionyl chloride) with one made from trans-4-bromomethyl-n-pentylcyclohexane Grignard solution] are mixed with 2.5 g of 85% hydrazine hydrate, 3.2 g of potassium hydroxide and 15 ml of triethylene glycol Boiled for 2 hours, then on the descending cooler until an internal temperature of 195 ° is reached heated and held at this temperature for 4 hours. After cooling and diluting with water, after Customary work-up 4.1 g of l-trans-4-pentylcyclohexyl-2- [5-pentylthieno [3,2-b] thien-2-yl] ethane obtain.

The following are produced in the same way:

l-trans -4-methylcyclohexyl-2- [5-pentylthieno [3,2-b] thien-2-yl] ethane 1-trans -4-ethylcyclohexyl-2- [5-pentylthieno [3,2-b] thien-2-yl Jethane 1-trans ^ -propylcyclohexyl ^ - [5-pentylthieno [3,2-b] thien-2-yl] ethane l-trans-4-butylcyclohexyl-2- [5-pentylthieno [3,2-b] thien-2-yl] ethane l-trans-4-heptylcyclohexyl-2- [5-pentylthieno [3,2-b] thien-2-yl] ethane l-trans-4-nonylcyclohexyl-2- [5-pentylthieno [3,2-b] thien-2-yl] ethane

PAT LOG 3/5 270983

1-trans -4-methylcyclohexyl-2- [5-propylthieno [3,2-b] thien-2-yl-ethane 1-trans -4-ethylcyclohexyl-2- [5-propylthieno [3,2-b] thien-2-yl] ethane 1-trans -4-propylcyclohexyl-2- [5-propylthieno [3,2-b] thien-2-yl] ethane 1-trans -4-butylcyclohexyl-2- [5-propylthieno [3,2-b] thien-2-yl] ethane 1-trans -4-pentylcyclohexyl-2- [5-propylthieno [3,2-b] thien-2-yl] ethane 1-trans -4-heptylcyclohexyl-2- [5-propylthieno [3,2-b] thien-2-yl] ethane l-trans-4-nonylcyclohexyl-2- [5-propylthieno [3,2-b] thien-

2-yl] ethane 15

1-trans -4-methylcyclohexyl-2- [5-heptylthieno [3,2-b] thien-2-yl] ethane 1-trans -4-ethylcyclohexyl-2- [5-heptylthieno [3,2-b] thien-2-yl] ethane 1-trans -4-propylcyclohexyl-2- [5-heptylthieno [3,2-b] thien-2-yl] ethane 1-trans -4-butylcyclohexyl-2- [5-heptylthieno [3,2-b] thien-2-yl] ethane 1-trans 1 - 3 pentylcyclohexyl 1 - [5-heptylthieno [3,2-b] thien-2-yl] ethane l-trans -4-heptylcyclohexyl-2- [5-heptylthieno [3,2-b] thien-2-yl] ethane l-trans-4-nonylcyclohexyl-2- [5-heptylthieno [3,2-b] thien-

2-yl] ethane 30

PAT LOG 3/5 270983

1-p-Ethylphenyl-2- [5-pentyl-thieno [2,3-b] thien-2-yl] ethane 1-p-Butylphenyl-2- [5-pentyl-thieno [2,3-b] thien-2-yl] ethane 1-p-Pentylphenyl-2- [5-pentyl-thieno [2,3-b] thien-2-yl] ethane 1-p-Heptylphenyl-2- [5-pentyl-thieno [2,3-b] thien-2-yl] ethane l-p -cyanophenyl-2- [5-pentyl-thieno [2,3-b] thien-2-yl] ethane 1-p-Fluorophenyl-2- [5-pentyl-thieno [2,3-b] thien-2-yl] ethane l-p-Chlorophenyl-2- [5-pentyl-thieno [2,3-b] thien-2-yl] -

ethane 15

l_4_Ethylcyclohexyl-2- [5-pentyl-thieno [2,3-b] thien-2-yl] ethane l «4_p _rO pyicyclohexyl-2- [5-pentyl-thieno [2,3-b] thien-2- yl] ethane 1-4-butylcyclohexyl-2- [5-pentyl-thieno [2,3-b] thien-2-yl] ethane 1-4-pentylcyclohexyl-2- [5-pentyl-thieno [2, 3-b] thien-2-yl] ethane 1- 4-heptylcyclohexyl-2- [5-pentyl-thieno [2,3-b] thien-2-yl] ethane.

Example 3

An alcoholate solution prepared from 1.9 g of sodium and 60 ml of ethanol is added dropwise at room temperature within a solution of 4.6 g of 3-p-cyanobenzylmercapto-2-formyl-5- (4-pentylcyclohexyl) thiophene over a period of 5 minutes in 25 ml of ethanol and then boiled for 5 hours. Customary work-up gives 2-p-cyanophenyl-5- (4-pentylcyclohexyl) -5 thieno [3,2-b] thiophene.

PAT LOG 3/5 270983

The following are produced in the same way:

2-p -cyanophenyl-5- (4-propylcyclohexyl) thieno [3,2-b] thiophene

2-p -cyanophenyl-5- (4-butylcyclohexyl) thieno [3,2-b] thiophene

2-p -cyanophenyl-5- (4-heptylcyclohexyl) thieno [3,2-b] thiophene

2-p -cyanophenyl-5- (4'-propylcyclohexylcyclohexyl) thieno [3,2-b] thiophene 2-p -cyanophenyl-5- (4'-butylcyclohexylcyclohexyl) thieno [3,2-b] thiophene 2-p -cyanophenyl-5- (4'-pentylcyclohexylcyclohexyl) thieno [3,2-b] thiophene 2-p -cyanophenyl-5- (4'-heptylcyclohexylcyclohexyl) thieno [3,2-b] thiophene

2-p-cyanopheny1-5- (ρ-4-propy1eye1ohexylpheny1) -0 thieno [3,2-b] thiophene 2-p -cyanophenyl-5- (p-4-butylcyclohexylphenyl) thieno [3,2-b] thiophene 2-p -cyanophenyl-5- (p-4-pentylcyclohexylphenyl) thieno [3,2-b] thiophene 2-p-Cyanophenyl-5- (p-4-heptylcyclohexylpheny1) -thi eno [3,2-b] thiophene.

Example 4

20.5 g of S-n-heptyl-S-chlorothienofS ^ -bJthiophene ^ -carboxylic acid chloride [obtainable by reacting 5-n-heptylthiophene-2-acrylic acid (from 5-n-heptylthiophene-2-carbaldehyde and malonic acid in the presence of pyridine / piperidine) with Thionyl chloride / pyridine in toluene] is made up with 13.6 g of 4-n-propylphenol and 8 g of pyridine in 100 ml of toluene for 4 hours 100 ° heated. Customary work-up gives 14.8 g of 4-n-propylphenyl (S-n-heptyl-3-chlorothieno [3,2-b] thiophene) -2-carboxylate.

- 3 «The following are produced in the same way:

4-Ethylphenyl (S-n -heptyl-3-chlorothieno [3,2-b] thiophene) -2-carboxylate 4-butylphenyl (5-n-heptyl-3-chlorothieno [3,2-b] thiophene) -2-carboxylate 4-pentylphenyl (S-n-heptyl-3-chlorothieno [3,2-b] thiophene) -2-carboxylate 4-heptylphenyl (5-n-heptyl-3-chlorothieno [3,2-b] thiophene) -2-carboxylate 4-nonylphenyl (5-n-heptyl-3-chlorothieno [3,2-b] thiophene) -2-carboxylate 4-cyanophenyl (5-n-heptyl-3-chlorothieno [3,2-b] thiophene) -2-carboxylate 4-fluorophenyl (5-n-heptyl-3-chlorothieno [3,2-b] thiophene) -2-carboxylate

4-Ethylcyclohexyl (5-n-heptyl-3-chlorothieno [3,2-b] thiophene) -2-carboxylate 4-propylcyclohexyl (5-n-heptyl-3-chlorothieno [3,2-b] thiophene) -2-carboxylate 4-butylcyclohexyl (5-n-heptyl-3-chlorothieno [3,2-b] thiophene) -2-carboxylate 4-pentylcyclohexyl (S-n-heptyl-3-chlorothieno [3,2-b] thiophene) 2-carboxylate 4-Heptylcyclohexyl- (5-n-heptyl-3-chlorothieno [3,2-b] thiophene) ■ 2-carboxylate 4-nonylcyclohexyl- (5-n-heptyl-3-chlorothieno [3,2-b] thiophene) -

2-carboxylate 30

PAT LOG 3/5 270983

Example 5

20.4 g of 5-n-octylthieno [2,3-b] thiophene-2-carbaldehyde (available from 2-n-octylthieno [2,3-b] thiophene by Vilsmeyer formylation with phosphorus oxychloride / dimethylformamide) and 9.5 g of 2-n-pentylpropane-1,3-diol are dissolved in 150 ml of toluene, and a spatula tip of toluenesulfonic acid is added and heated on the water separator until no more water separates out. It is washed with sodium hydrogen carbonate solution the acid is dried out over sodium sulfate and the toluene is distilled off. The pure trans-2- (5n-octylthienof2,3-b] thien-2-yl) -5-n-pentyl-1,3-dioxane obtained by repeated recrystallization from ethanol (17.5 g).

The following are produced in the same way:

2- (5-n-Octylthieno [2,3-b] thien-2-yl) -5-ethyl-1,3-dioxane 2- (5-n-Octylthieno [2,3-b] thien-2-yl) -5-propyl-1,3-dioxane 2- (5-n-Octylthieno [2,3-b] thien-2-yl) -5-butyl-1,3-dioxane 2- (5-n-Octylthieno [2,3-b] thien-2-yl) -5-heptyl-1,3-dioxane 2- (5-n-Octylthieno [2,3-b] thien-2-yl) -5-nonyl-1,3-dioxane

2- (5-n-Pentylthieno [2,3-b] thien-2-yl) -5-ethyl-1,3-dioxane 2- (5-n-Pentylthieno [2,3-b] thien-2-yl) -5-propyl-1,3-dioxane 2- (5-n-Pentylthieno [2,3-b] thien-2-yl) -5-butyl-1,3-dioxane 2- (5-n-Pentylthieno [2,3-b] thien-2-yl) -5-pentyl-1,3-dioxane 2- (5-n-Pentylthieno [2,3-b] thien-2-yl) -5-heptyl-1,3-dioxane 2- (5-n-Pentylthieno [2,3-b] thien-2-yl) -5-nonyl-1,3-dioxane

2- (5-n-Propylthieno [2,3-b] thien-2-yl) -5-ethyl-1,3-dioxane 2- (5-n-Propylthieno [2,3-b] thien-2-yl) -5-propyl-1,3-dioxane 2- (5-n-Propylthieno [2,3-b] thien-2-yl) -5-butyl-1,3-dioxane 2- (5-n-Propylthieno [2,3-b] thien-2-yl) -5-pentyl-1,3-dioxane 2- (5-n-Propylthieno [2,3-b] thien-2-yl) -5-heptyl-1,3-dioxane 2- (5-n-Propylthieno [2,3-b] thien-2-yl) -5-nonyl-1,3-dioxane

PAT LOG 3/5 270983

2- (5-Cyanthieno [2,3-b] thien-2-yl) -5-ethyl-1,3-dioxane 2- (5-Cyanthieno [2,3-b] thien-2-yl) -5-propyl-1,3-dioxane 2- (5-Cyanthieno [2,3-b] thien-2-yl) -5-butyl-1,3-dioxane 2- (5-Cyanthieno [2,3-b] thien-2-yl) -5-pentyl-1,3-dioxane 2- (5-Cyanthieno [2,3-b] thien-2-yl) -5-heptyl-1,3-dioxane 2- (5-Cyanthieno [2,3-b] thien-2-yl) -5-nonyl-1,3-dioxane

2- (5-Cyanthieno [2,3-b] thien-2-yl) -5- (4-ethylcyclohexyl) -1,3-dioxane 2- (5-Cyanthieno [2,3-b] thien-2-yl) -5- (4-propylcyclohexyl) -1,3-dioxane 2- (5-Cyanthieno [2,3-b] thien-2-yl) -5- (4-butylcyclohexyl) -1,3-dioxane 2- (5-Cyanthieno [2,3-b] thien-2-yl) -5- (4-pentylcyclohexyl) -1,3-dioxane 2- (5-Cyanthieno [2,3-b] thien-2-yl) -5- (4-heptylcyclohexyl) -1,3-dioxane 2- (5-Cyanthieno [2,3-b] thien-2-yl) -5- (4-nonylcyclohexyl) -

1,3-dioxane 20

Example 6

19 g of 2- [4- (trans-4-n-propylcyclohexyl) styryl] -5-n-pentylthiophene (obtainable by Friedel-Crafts acylation of 2-pentylthiophene with 4- (trans-4-n-propylcyclohexyl) phenylacetyl chloride, Reduction of the resulting ketone with sodium boronate to alcohol and subsequent dehydration) and 5 g of sulfur are heated to 220 ° for 3 hours. Subsequent chromatographic work-up gives 8.3 g 2- [4-trans -4- n -propylcyclohexylphenyl] -5- n -pentylthieno [3,2-b] thiophene.

PAT LOG 3/5 270983

The following are produced in the same way:

2- [4- (trans -4-Ethylcyclohexyl) phenyl] -5-n -pentylthieno [3,2-b] thiophene 2- [4- (trans -4-Butylcyclohexyl) phenyl] -5-n -pentylthieno [3,2-b] thiophene 2- [4- (trans-4-pentylcyclohexyl) phenyl] -5-n-pentyl thi eno [3,2-b] thiophene 2- [4- (trans-4-heptylcyclohexyl) phenyl] -5-n-pentyl thieno [3,2-b] thiophene 2- [4- (trans -4-nonylcyclohexyl) phenyl] -5-n -pentylthieno [3,2-b] thiophene

2- [4- (trans -4-Ethylcyclohexyl) phenyl] -5- n -heptylthieno [3,2-b] thiophene 2- [4- (trans -4-Butylcyclohexyl) phenyl] -5- n -heptylthieno [3,2-b] thiophene 2- [4- (trans-4-pentylcyclohexyl) phenyl] -5-n-heptyl thieno [3,2-b] thiophene 2- [4- (trans-4-heptylcyclohexyl) phenyl] -5-n-heptyl thieno [3,2-b] thiophene 2- [4- (trans -4-Nonylcyclohexyl) phenyl] -5- n -heptylthieno [3,2-b] thiophene

2- [4- (trans -4-Ethylcyclohexyl) phenyl] -5-cyanthieno [3,2-b] thiophene 2- [4- (trans -4-Butylcyclohexyl) phenyl] -5-cyanthieno [3,2-b] thiophene 2- [4- (trans-4-pentylcyclohexyl) phenyl] -5-cyanthieno [3,2-b] thiophene 2- [4- (trans -4-heptylcyclohexyl) phenyl] -5-cyanthieno [3,2-b] thiophene 2- [4- (trans-4-nonylcyclohexyl) phenyl] -5-cyano-

thieno [3,2-b] thiophene 35

PAT LOG 3/5 270983

2- [trans, trans -4'-ethylcyclohexylcyclohexyl] -5-cyanthi eno [3,2-b] thiophene 2- [trans, trans-4'-butylcyclohexylcyclohexyl] -5-cyanthieno [3,2-b] thiophene 2- [trans, trans-4'-pentylcyclohexylcyclohexyl] -5-cyanthieno [3,2-b] thiophene 2- [trans, trans-4'-heptylcyclohexylcyclohexyl] -5-cyanthieno [3,2-b] thiophene 2- [trans, trans-4'-nonylcyclohexylcycloheyxl] -5-cyanthieno [3,2-b] thiophene

The following are examples of liquid-crystalline phases according to the invention with a content of at least one Ver bond of formula I: 15

Example A.

A liquid crystalline phase

15% p-trans-4-ethylcyclohexylbenzonitrile, 15% p-trans-4-butylcyclohexylbenzonitrile,

10% 4-ethyl-4'-cyanbiphenyl, 13% 4-butyl-4'-cyanbiphenyl,

11% 4-cyano-4 '- (trans-4-pentylcyclohexyl) -biphenyl, 6% 4-p-cyanophenyl-4'-pentylbiphenyl, 15% 5-pentylthieno [3,2-b] thiophene-2-carboxylic acid

4-pentylphenyl ester and 15% 5-propylthieno [3,2-b] thiophene-2-carboxylic acid

4-propylphenyl ester 30

has a melting point of -8 °, a clearing point of and a viscosity of 29 cSt.

PAT LOG 3/5 270983

Example B.

A liquid crystalline phase

8% 2-p-cyanophenyl-5-ethyl-1,3-dioxane, 9% 2-p-cyanophenyl-5-propyl-1,3-dioxane,

4% p-ethylbenzoic acid (p-cyanophenyl ester,

3% p-propylbenzoic acid (p-cyanophenyl ester),

11% p-trans-4-ethylcyclohexylbenzonitrile, 13% p-trans-4-butylcyclohexylbenzonitrile,

8% 4-ethyl-4'-cyanobiphenyl,

12% 4-butyl-4'-cyanobiphenyl,

5% p-trans-4-pentylcyclohexylbenzoic acid

(p-cyanophenyl ester), 9% S-propylthienoCS ^ -bJthiophene-a-carboxylic acid 4-cyanophenyl ester,

9% 5-pentylthieno [3,2-b] thiophene-2-carboxylic acid

4-cyanophenyl ester and

9% 5-heptylthieno [3,2-b] thiophene-2-carboxylic acid 4-cyanophenyl ester

has a melting point of -11 °, a clearing point of 61 ° and a viscosity of 36 cSt. An electro-optical display element with this phase as the dielectric has a low threshold voltage of V ₁₀ = 1.15 V.

Example C

A liquid crystalline phase from 30

10% 2-p-cyanophenyl-5-ethyl-1,3-dioxane, 10% 2-p-cyanophenyl-5-propyl-1,3-dioxane, 16% 2-p-cyanophenyl-5-butyl-1,3-dioxane,

PAT LOG 3/5 270983

10% a-p-cyanophenyl-S-pentyl-l ^ -dioxane, 18% 5-propylthieno [3,2-b] thiophene-2-carboxylic acid 4-propylphenyl ester,

18% 5-pentylthieno [3,2-b] thiophene-2-carboxylic acid 4-pentylphenyl ester and

18% 5-pentylthieno [3,2-b] thiophene-2-carboxylic acid 4-heptylphenyl ester

has a melting point of -10 °, a clearing point of 62 'and a viscosity of 31 cSt.

Example D

A liquid crystalline phase from 15

4% 2-p-cyanophenyl-5-propyl-1,3-dioxane,

5% 2-p-cyanophenyl-5-butyl-1,3-dioxane, 4% 2-p-cyanophenyl-5-pentyl-1,3-dioxane,

10% trans ^ -propylcyclohexanecarboxylic acid ip-methoxyphenyl ester),

11% trans-4-propylcyclohexanecarboxylic acid (p-ethoxy-

phenyl ester),
15% trans-4-butylcyclohexanecarboxylic acid (p-methoxyphenyl ester),
10% trans-4-butylcyclohexanecarboxylic acid (p-ethoxy-

phenyl ester),
10% trans-4-pentylcyclohexanecarboxylic acid (p-methoxyphenyl ester),

13% trans-4-pentylcyclohexanecarboxylic acid (p-pentyl-0 phenyl ester),

6% 5-propylthieno [3,2-b] thiophene-2-carboxylic acid-4-

cyanophenyl ester,

PAT LOG 3/5 270983

-Αί-

7% 5-pentylthieno [3,2-b] thiophene-2-carboxylic acid 4-cyanophenyl ester and

5% 5-heptylthieno [3,2-b] thiophene-2-carboxylic acid 4-cyanophenyl ester

has a melting point of -12 °, a clearing point of and a viscosity of 18 cSt. In an electro-optical The display element shows this dielectric good multiplex properties (1:32).

Example E.

A liquid crystalline phase from 15

18.0% p-trans-4-propylcyclohexylbenonitrile, 13.5% p-trans-4-butylcyclohexylbenonitrile, 24.5% p-trans-4-pentylcyclohexylbenonitrile, 15.5% p-trans-4-heptylcyclohexylbenonitrile, 7, 0% 4-cyano-4 ^l - (trans-4-pentylcyclohexyl) -biphenyl, 7.0% 4- (trans-4-pentylcyclohexyl) -4 '- (trans-4-

propylcyclohexyl) biphenyl, 6.0% 4-p-cyanophenyl-4'-pentyl-biphenyl, 8.0% trans-4-butylcyclohexanecarboxylic acid (p-transpropylcyclohexylphenyl ester) and

0.5% 5-pentylthieno [3,2-b] thiophene-2-carboxylic acid 4-cyanophenyl ester

has a melting point of -14 ° and a clearing point of 88 °.

PAT LOG 3/5 270983

JL m

-Wf- example F
A liquid crystalline phase

14% p-trans-4-propylcyclohexylbenzonitrile, 16% 2-p-cyanophenyl-5-butyl-1,3-dioxane, 10% 2-p-cyanophenyl-5-pentyl-1,3-dioxane, 14% 5-propylthieno [3,2-b] thiophene-2-carboxylic acid 4-cyanophenyl ester, 10% 5-pentylthieno [3,2-b] thiophene-2-carboxylic acid-4-

cyanophenyl ester, 8% 5-heptylthieno [3,2-b] thiophene-2-carboxylic acid 4-cyanophenyl ester,

16% 5-propyl-thieno [3,2-b] thiophene-2-carboxylic acid 4-propylphenyl ester and

12% 5-pentyl-thieno [3,2-b] thiophene-2-carboxylic acid 4-pentylphenyl ester

is a good host material for pleochroism dyes.

Example G
A liquid crystalline phase

66.6% p-methoxybenzoic acid (p-pentylphenyl ester),

33.3% p-hexoxybenzoic acid (p-pentylphenyl ester) and

0.1% 5-propylthieno [3,2-b] thiophene-2-carboxylic acid

4-propylphenyl ester

has a melting point of 13 °.

PAT LOG 3/5 270983

Claims (6)

Merck Patent Limited Liability Company 15 Darmstadt Claims: \ 1.) Thi eno thi ophender i vate of the formula I. 11 1 7 2 R- (Α " ¹ ) _m -Z ¹ -A- (Z ^Z -hT ) _n -R ^ wherein 1 R and R each have H, an alkyl group with 30 1-10 carbon atoms, in which also one or two CH ₂ groups can be replaced by O atoms, F, Cl, Br, CN, -COOR or -O-COR, PAT LOG 3/6 270983 "I - '. J FOLLOW-UP CR Π ¹ 1 - r- 1 2
A and A each unsubstituted or substituted by one or two F, Cl, Br atoms and / or CN groups and / or CH ₃ groups, 1,4-phenylene, 1,4-cyclohexylene, 1,3 -Dioxane-2,5-diyl-, 1,3-dithiane-2,5-diyl, tetrahydropyran-2,5-diyl, Pyridazine-3,6-diyl, piperidine-1,4-diyl-, 1,4-bicyclo (2,2,2) octylene, or pyrimidine-2,5-diyl groups, A an unsubstituted or by an or groups of formula 1 or 2 substituted by two Cl and / or Br atoms -CO- Z ¹ and Z ² each -CO-O-, -0-CO-, -CH ₂ CH ₂ -, - pO or a single bond, R is an alkyl group with 1-10 C atoms, m 1 or 2 and
η 0 or 1
mean, where for m = 2 the two groups A can be identical to or different from one another. 2. Process for the preparation of thienothiophene derivatives of the formula I according to Claim 1, characterized in that that one is a compound which otherwise corresponds to the formula I, but instead of Η atoms one or contains several reducible groups and / or C-C bonds, treated with a reducing agent, PAT LOG 3/6 270983 or that for the preparation of esters of the formula I 1 2 (where R and / or R are -O-COR or -COOR 1 2 and / or where Z and / or Z are -CO-O- or -0-C0-) a corresponding carboxylic acid or one of its reactive derivatives with a corresponding one Converts alcohol or one of its reactive derivatives, or that for the preparation of dioxane derivatives 1 2 of the formula I (in which A and / or A 1,3-dioxane-2,5-diyl mean) reacts a corresponding aldehyde with a corresponding diol, or that for the production of nitriles the 1 2 Formula I (where R and / or R denote CN) a corresponding carboxamide is dehydrated or a corresponding carboxylic acid halide reacts with sulfamide, or that a thiophene derivative of the formula II, , 3 p II wherein 1 2
one of the residues Q and Q -CHO, the other -SCH ₂ -Q ³ and Q ³ R ^1- - (A ¹ J _1n -Z ¹ - or R ² - (A ² -Z ² ) _n ~ means condensed,
30th or that for the production of ethers of the form 1 2 mel I (in which R and / or R denotes an alkyl group, in which one or two CH ₀ groups through I 2 O atoms are replaced and / or Z and / or Z are a PAT LOG 3/6 270983 -OCH ₂ - or -CH ₂ O-GrUpPe) etherifies a corresponding hydroxy compound, and / or that optionally a chlorine or bromine compound of the formula I (in which R and / or ο
R is Cl or Br) with a cyanide. 3. Use of the compounds of the formula I according to claim 1 as components of liquid-crystalline Phases. 4. Liquid-crystalline phase, characterized in that it contains at least one compound of the formula I. contains. 5. Liquid crystal display element, characterized in that it is a liquid crystalline phase according to claim 4 contains. 6. Electro-optical display element, characterized in that it is a liquid-crystalline Dielectric contains a liquid-crystalline phase according to claim 4. PAT LOG 3/6 270983